Portal:Trains/Selected article/Week 3, 2021

Paris Métro Line 12 (opened as Line A) is one of the sixteen lines of the Paris Métro. It links Issy-les-Moulineaux, a suburban town southwest of Paris, to Front Populaire, on the border between Saint-Denis and Aubervilliers in the north. It has several important stops, such as Madeleine, the 6th arrondissement of Paris, Porte de Versailles and two national railway stations, Gare Montparnasse and Gare Saint-Lazare. Line 12 was founded as Line A by the Nord-Sud Company, who also built Line 13. It was built between 1905 and 1910, to connect the districts of Montparnasse, in the south, and Montmartre, in the north. The first trip, from Porte de Versailles to Notre-Dame-de-Lorette, was on 5 November 1910. The line was the second to be built on the north–south axis of the city, in competition with Line 4 of the Compagnie du chemin de fer métropolitain de Paris (CMP; Paris Metropolitan Railway Company). It was extended bit by bit until 1934 when it reached Mairie d'Issy in the south. Tunnelling to the northern terminus at the Porte de la Chapelle on the perimeter of Paris had been completed in 1916. In 1930, the CMP bought the Nord-Sud company and Line A was integrated into the new, unified network as Line 12. In 1949, the CMP was itself merged into the RATP, Paris's public transport company. They operate the line today and have plans to extend it south as far as the town of Issy-les-Moulineaux and north to La Plaine in Saint-Denis. The line was built using cut-and-cover excavation techniques. Since this method cannot be used under buildings, the route follows the streets above. It remains unchanged today and many original design features, such as the Nord-Sud company's refined ceramic decor, remain in the stations.